2 * linux/arch/arm/drivers/block/mfmhd.c
4 * Copyright (C) 1995, 1996 Russell King, Dave Alan Gilbert (gilbertd@cs.man.ac.uk)
6 * MFM hard drive code [experimental]
12 * 3/2/96:DAG: Started a change list :-)
13 * Set the hardsect_size pointers up since we are running 256 byte
15 * Added DMA code, put it into the rw_intr
16 * Moved RCAL out of generic interrupt code - don't want to do it
17 * while DMA'ing - its now in individual handlers.
18 * Took interrupt handlers off task queue lists and called
19 * directly - not sure of implications.
21 * 18/2/96:DAG: Well its reading OK I think, well enough for image file code
22 * to find the image file; but now I've discovered that I actually
23 * have to put some code in for image files.
25 * Added stuff for image files; seems to work, but I've not
26 * got a multisegment image file (I don't think!).
27 * Put in a hack (yep a real hack) for multiple cylinder reads.
28 * Not convinced its working.
30 * 5/4/96:DAG: Added asm/hardware.h and use IOC_ macros
31 * Rewrote dma code in mfm.S (again!) - now takes a word at a time
32 * from main RAM for speed; still doesn't feel speedy!
34 * 20/4/96:DAG: After rewriting mfm.S a heck of a lot of times and speeding
35 * things up, I've finally figured out why its so damn slow.
36 * Linux is only reading a block at a time, and so you never
37 * get more than 1K per disc revoloution ~=60K/second.
39 * 27/4/96:DAG: On Russell's advice I change ll_rw_blk.c to ask it to
40 * join adjacent blocks together. Everything falls flat on its
42 * Four hours of debugging later; I hadn't realised that
43 * ll_rw_blk would be so generous as to join blocks whose
44 * results aren't going into consecutive buffers.
46 * OK; severe rehacking of mfm_rw_interrupt; now end_request's
47 * as soon as its DMA'd each request. Odd thing is that
48 * we are sometimes getting interrupts where we are not transferring
49 * any data; why? Is that what happens when you miss? I doubt
50 * it; are we too fast? No - its just at command ends. Got 240K/s
51 * better than before, but RiscOS hits 480K/s
53 * 25/6/96:RMK: Fixed init code to allow the MFM podule to work. Increased the
54 * number of errors for my Miniscribe drive (8425).
56 * 30/6/96:DAG: Russell suggested that a check drive 0 might turn the LEDs off
57 * - so in request_done just before it clears Busy it sends a
58 * check drive 0 - and the LEDs go off!!!!
60 * Added test for mainboard controller. - Removes need for separate
63 * 13/7/96:DAG: Changed hardware sectore size to 512 in attempt to make
65 * 21/7/96:DAG: Took out old image file stuff (accessing it now produces an IO
68 * 17/8/96:DAG: Ran through indent -kr -i8; evil - all my nice 2 character indents
69 * gone :-( Hand modified afterwards.
70 * Took out last remains of the older image map system.
72 * 22/9/96:DAG: Changed mfm.S so it will carry on DMA'ing til; BSY is dropped
73 * Changed mfm_rw_intr so that it doesn't follow the error
74 * code until BSY is dropped. Nope - still broke. Problem
75 * may revolve around when it reads the results for the error
78 *16/11/96:DAG: Modified for 2.0.18; request_irq changed
80 *17/12/96:RMK: Various cleanups, reorganisation, and the changes for new IO system.
81 * Improved probe for onboard MFM chip - it was hanging on my A5k.
82 * Added autodetect CHS code such that we don't rely on the presence
83 * of an ADFS boot block. Added ioport resource manager calls so
84 * that we don't clash with already-running hardware (eg. RiscPC Ether
85 * card slots if someone tries this)!
87 * 17/1/97:RMK: Upgraded to 2.1 kernels.
89 * 4/3/98:RMK: Changed major number to 21.
91 * 27/6/98:RMK: Changed asm/delay.h to linux/delay.h for mdelay().
95 * Possible enhancements:
96 * Multi-thread the code so that it is possible that while one drive
97 * is seeking, the other one can be reading data/seeking as well.
98 * This would be a performance boost with dual drive systems.
101 #include <linux/module.h>
102 #include <linux/config.h>
103 #include <linux/sched.h>
104 #include <linux/fs.h>
105 #include <linux/interrupt.h>
106 #include <linux/kernel.h>
107 #include <linux/timer.h>
108 #include <linux/mm.h>
109 #include <linux/errno.h>
110 #include <linux/genhd.h>
111 #include <linux/major.h>
112 #include <linux/ioport.h>
113 #include <linux/delay.h>
114 #include <linux/blkpg.h>
116 #include <asm/system.h>
119 #include <asm/uaccess.h>
121 #include <asm/hardware.h>
122 #include <asm/ecard.h>
123 #include <asm/hardware/ioc.h>
125 static void (*do_mfm)(void) = NULL;
126 static struct request_queue *mfm_queue;
127 static DEFINE_SPINLOCK(mfm_lock);
129 #define MAJOR_NR MFM_ACORN_MAJOR
130 #define QUEUE (mfm_queue)
131 #define CURRENT elv_next_request(mfm_queue)
133 * This sort of stuff should be in a header file shared with ide.c, hd.c, xd.c etc
136 #define HDIO_GETGEO 0x301
139 unsigned char sectors;
140 unsigned short cylinders;
147 * Configuration section
149 * This is the maximum number of drives that we accept
151 #define MFM_MAXDRIVES 2
153 * Linux I/O address of onboard MFM controller or 0 to disable this
155 #define ONBOARD_MFM_ADDRESS ((0x002d0000 >> 2) | 0x80000000)
157 * Uncomment this to enable debugging in the MFM driver...
163 * End of configuration
168 * This structure contains all information to do with a particular physical
172 unsigned char sectors;
174 unsigned short cylinders;
175 unsigned short lowcurrent;
176 unsigned short precomp;
178 #define NEED_1_RECAL -2
179 #define NEED_2_RECAL -3
186 } mfm_info[MFM_MAXDRIVES];
188 #define MFM_DRV_INFO mfm_info[raw_cmd.dev]
190 /* Stuff from the assembly routines */
191 extern unsigned int hdc63463_baseaddress; /* Controller base address */
192 extern unsigned int hdc63463_irqpolladdress; /* Address to read to test for int */
193 extern unsigned int hdc63463_irqpollmask; /* Mask for irq register */
194 extern unsigned int hdc63463_dataptr; /* Pointer to kernel data space to DMA */
195 extern int hdc63463_dataleft; /* Number of bytes left to transfer */
200 static int lastspecifieddrive;
201 static unsigned Busy;
203 static unsigned int PartFragRead; /* The number of sectors which have been read
204 during a partial read split over two
205 cylinders. If 0 it means a partial
206 read did not occur. */
208 static unsigned int PartFragRead_RestartBlock; /* Where to restart on a split access */
209 static unsigned int PartFragRead_SectorsLeft; /* Where to restart on a split access */
211 static int Sectors256LeftInCurrent; /* i.e. 256 byte sectors left in current */
212 static int SectorsLeftInRequest; /* i.e. blocks left in the thing mfm_request was called for */
213 static int Copy_Sector; /* The 256 byte sector we are currently at - fragments need to know
214 where to take over */
215 static char *Copy_buffer;
218 static void mfm_seek(void);
219 static void mfm_rerequest(void);
220 static void mfm_request(void);
221 static void mfm_specify (void);
222 static void issue_request(unsigned int block, unsigned int nsect,
223 struct request *req);
225 static unsigned int mfm_addr; /* Controller address */
226 static unsigned int mfm_IRQPollLoc; /* Address to read for IRQ information */
227 static unsigned int mfm_irqenable; /* Podule IRQ enable location */
228 static unsigned char mfm_irq; /* Interrupt number */
229 static int mfm_drives = 0; /* drives available */
230 static int mfm_status = 0; /* interrupt status */
233 static struct rawcmd {
235 unsigned int cylinder;
238 unsigned int cmdtype;
239 unsigned int cmdcode;
240 unsigned char cmddata[16];
244 static unsigned char result[16];
247 void (*interrupt) (void); /* interrupt handler */
248 void (*error) (void); /* error handler */
249 void (*redo) (void); /* redo handler */
250 void (*done) (int st); /* done handler */
254 static struct tq_struct mfm_tq = {0, 0, (void (*)(void *)) NULL, 0};
257 int number_mfm_drives = 1;
259 /* ------------------------------------------------------------------------------------------ */
261 * From the HD63463 data sheet from Hitachi Ltd.
264 #define MFM_COMMAND (mfm_addr + 0)
265 #define MFM_DATAOUT (mfm_addr + 1)
266 #define MFM_STATUS (mfm_addr + 8)
267 #define MFM_DATAIN (mfm_addr + 9)
269 #define CMD_ABT 0xF0 /* Abort */
270 #define CMD_SPC 0xE8 /* Specify */
271 #define CMD_TST 0xE0 /* Test */
272 #define CMD_RCLB 0xC8 /* Recalibrate */
273 #define CMD_SEK 0xC0 /* Seek */
274 #define CMD_WFS 0xAB /* Write Format Skew */
275 #define CMD_WFM 0xA3 /* Write Format */
276 #define CMD_MTB 0x90 /* Memory to buffer */
277 #define CMD_CMPD 0x88 /* Compare data */
278 #define CMD_WD 0x87 /* Write data */
279 #define CMD_RED 0x70 /* Read erroneous data */
280 #define CMD_RIS 0x68 /* Read ID skew */
281 #define CMD_FID 0x61 /* Find ID */
282 #define CMD_RID 0x60 /* Read ID */
283 #define CMD_BTM 0x50 /* Buffer to memory */
284 #define CMD_CKD 0x48 /* Check data */
285 #define CMD_RD 0x40 /* Read data */
286 #define CMD_OPBW 0x38 /* Open buffer write */
287 #define CMD_OPBR 0x30 /* Open buffer read */
288 #define CMD_CKV 0x28 /* Check drive */
289 #define CMD_CKE 0x20 /* Check ECC */
290 #define CMD_POD 0x18 /* Polling disable */
291 #define CMD_POL 0x10 /* Polling enable */
292 #define CMD_RCAL 0x08 /* Recall */
294 #define STAT_BSY 0x8000 /* Busy */
295 #define STAT_CPR 0x4000 /* Command Parameter Rejection */
296 #define STAT_CED 0x2000 /* Command end */
297 #define STAT_SED 0x1000 /* Seek end */
298 #define STAT_DER 0x0800 /* Drive error */
299 #define STAT_ABN 0x0400 /* Abnormal end */
300 #define STAT_POL 0x0200 /* Polling */
302 /* ------------------------------------------------------------------------------------------ */
304 static void console_printf(const char *fmt,...)
306 static char buffer[2048]; /* Arbitary! */
307 extern void console_print(const char *);
311 local_irq_save(flags);
314 vsprintf(buffer, fmt, ap);
315 console_print(buffer);
318 local_irq_restore(flags);
319 }; /* console_printf */
321 #define DBG(x...) console_printf(x)
326 static void print_status(void)
329 static char *errors[] = {
346 "data field EEC error",
347 "data field CRC error",
349 "data field fatal error",
352 "ID field CRC error",
357 if (result[1] < 0x65)
358 error = errors[result[1] >> 2];
362 if (mfm_status & STAT_BSY) printk("BSY ");
363 if (mfm_status & STAT_CPR) printk("CPR ");
364 if (mfm_status & STAT_CED) printk("CED ");
365 if (mfm_status & STAT_SED) printk("SED ");
366 if (mfm_status & STAT_DER) printk("DER ");
367 if (mfm_status & STAT_ABN) printk("ABN ");
368 if (mfm_status & STAT_POL) printk("POL ");
369 printk(") SSB = %X (%s)\n", result[1], error);
373 /* ------------------------------------------------------------------------------------- */
375 static void issue_command(int command, unsigned char *cmdb, int len)
380 console_printf("issue_command: %02X: ", command);
381 for (i = 0; i < len; i++)
382 console_printf("%02X ", cmdb[i]);
383 console_printf("\n");
387 status = inw(MFM_STATUS);
388 } while (status & (STAT_BSY | STAT_POL));
389 DBG("issue_command: status after pol/bsy loop: %02X:\n ", status >> 8);
391 if (status & (STAT_CPR | STAT_CED | STAT_SED | STAT_DER | STAT_ABN)) {
392 outw(CMD_RCAL, MFM_COMMAND);
393 while (inw(MFM_STATUS) & STAT_BSY);
395 status = inw(MFM_STATUS);
396 DBG("issue_command: status before parameter issue: %02X:\n ", status >> 8);
399 outw(cmdb[1] | (cmdb[0] << 8), MFM_DATAOUT);
403 status = inw(MFM_STATUS);
404 DBG("issue_command: status before command issue: %02X:\n ", status >> 8);
406 outw(command, MFM_COMMAND);
407 status = inw(MFM_STATUS);
408 DBG("issue_command: status immediately after command issue: %02X:\n ", status >> 8);
411 static void wait_for_completion(void)
413 while ((mfm_status = inw(MFM_STATUS)) & STAT_BSY);
416 static void wait_for_command_end(void)
420 while (!((mfm_status = inw(MFM_STATUS)) & STAT_CED));
422 for (i = 0; i < 16;) {
424 in = inw(MFM_DATAIN);
425 result[i++] = in >> 8;
428 outw (CMD_RCAL, MFM_COMMAND);
431 /* ------------------------------------------------------------------------------------- */
433 static void mfm_rw_intr(void)
435 int old_status; /* Holds status on entry, we read to see if the command just finished */
437 console_printf("mfm_rw_intr...dataleft=%d\n", hdc63463_dataleft);
441 /* Now don't handle the error until BSY drops */
442 if ((mfm_status & (STAT_DER | STAT_ABN)) && ((mfm_status&STAT_BSY)==0)) {
443 /* Something has gone wrong - let's try that again */
444 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
446 DBG("mfm_rw_intr: DER/ABN err\n");
453 /* OK so what ever happened it's not an error, now I reckon we are left between
454 a choice of command end or some data which is ready to be collected */
455 /* I think we have to transfer data while the interrupt line is on and its
456 not any other type of interrupt */
457 if (CURRENT->cmd == WRITE) {
458 extern void hdc63463_writedma(void);
459 if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) {
460 printk("mfm_rw_intr: Apparent DMA write request when no more to DMA\n");
469 extern void hdc63463_readdma(void);
470 if ((hdc63463_dataleft <= 0) && (!(mfm_status & STAT_CED))) {
471 printk("mfm_rw_intr: Apparent DMA read request when no more to DMA\n");
478 DBG("Going to try read dma..............status=0x%x, buffer=%p\n", mfm_status, hdc63463_dataptr);
482 if (hdc63463_dataptr != ((unsigned int) Copy_buffer + 256)) {
483 /* If we didn't actually manage to get any data on this interrupt - but why? We got the interrupt */
484 /* Ah - well looking at the status its just when we get command end; so no problem */
485 /*console_printf("mfm: dataptr mismatch. dataptr=0x%08x Copy_buffer+256=0x%08p\n",
486 hdc63463_dataptr,Copy_buffer+256);
489 Sectors256LeftInCurrent--;
493 /* We have come to the end of this request */
494 if (!Sectors256LeftInCurrent) {
495 DBG("mfm: end_request for CURRENT=0x%p CURRENT(sector=%d current_nr_sectors=%d nr_sectors=%d)\n",
496 CURRENT, CURRENT->sector, CURRENT->current_nr_sectors, CURRENT->nr_sectors);
498 CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
499 CURRENT->sector += CURRENT->current_nr_sectors;
500 SectorsLeftInRequest -= CURRENT->current_nr_sectors;
502 end_request(CURRENT, 1);
503 if (SectorsLeftInRequest) {
504 hdc63463_dataptr = (unsigned int) CURRENT->buffer;
505 Copy_buffer = CURRENT->buffer;
506 Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2;
507 errors = &(CURRENT->errors);
508 /* These should match the present calculations of the next logical sector
510 Copy_Sector=CURRENT->sector*2; */
512 if (Copy_Sector != CURRENT->sector * 2)
514 /*console_printf*/printk("mfm: Copy_Sector mismatch. Copy_Sector=%d CURRENT->sector*2=%d\n",
515 Copy_Sector, CURRENT->sector * 2);
517 printk("mfm: Copy_Sector mismatch! Eek!\n");
520 }; /* Sectors256LeftInCurrent */
523 old_status = mfm_status;
524 mfm_status = inw(MFM_STATUS);
525 if (mfm_status & (STAT_DER | STAT_ABN)) {
526 /* Something has gone wrong - let's try that again */
528 DBG("mfm_rw_intr: DER/ABN error\n");
535 /* If this code wasn't entered due to command_end but there is
536 now a command end we must read the command results out. If it was
537 entered like this then mfm_interrupt_handler would have done the
539 if ((!((old_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) &&
540 ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR)) {
544 in = inw(MFM_DATAIN);
545 result[len++] = in >> 8;
550 /*console_printf ("mfm_rw_intr nearexit [%02X]\n", __raw_readb(mfm_IRQPollLoc)); */
552 /* If end of command move on */
553 if (mfm_status & (STAT_CED)) {
554 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
555 /* End of command - trigger the next command */
559 DBG("mfm_rw_intr: returned from cont->done\n");
561 /* Its going to generate another interrupt */
562 do_mfm = mfm_rw_intr;
566 static void mfm_setup_rw(void)
568 DBG("setting up for rw...\n");
570 do_mfm = mfm_rw_intr;
571 issue_command(raw_cmd.cmdcode, raw_cmd.cmddata, raw_cmd.cmdlen);
574 static void mfm_recal_intr(void)
577 console_printf("recal intr - status = ");
580 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
581 if (mfm_status & (STAT_DER | STAT_ABN)) {
582 printk("recal failed\n");
583 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
590 /* Thats seek end - we are finished */
591 if (mfm_status & STAT_SED) {
592 issue_command(CMD_POD, NULL, 0);
593 MFM_DRV_INFO.cylinder = 0;
597 /* Command end without seek end (see data sheet p.20) for parallel seek
598 - we have to send a POL command to wait for the seek */
599 if (mfm_status & STAT_CED) {
600 do_mfm = mfm_recal_intr;
601 issue_command(CMD_POL, NULL, 0);
604 printk("recal: unknown status\n");
607 static void mfm_seek_intr(void)
610 console_printf("seek intr - status = ");
613 outw(CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
614 if (mfm_status & (STAT_DER | STAT_ABN)) {
615 printk("seek failed\n");
616 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
623 if (mfm_status & STAT_SED) {
624 issue_command(CMD_POD, NULL, 0);
625 MFM_DRV_INFO.cylinder = raw_cmd.cylinder;
629 if (mfm_status & STAT_CED) {
630 do_mfm = mfm_seek_intr;
631 issue_command(CMD_POL, NULL, 0);
634 printk("seek: unknown status\n");
637 /* IDEA2 seems to work better - its what RiscOS sets my
638 * disc to - on its SECOND call to specify!
643 #define SPEC_SH 0xa9 /* Step pulse high=21, Record Length=001 (256 bytes) */
645 #define SPEC_SL 0x00 /* OM2 - SL - step pulse low */
646 #define SPEC_SH 0x21 /* Step pulse high=4, Record Length=001 (256 bytes) */
649 static void mfm_setupspecify (int drive, unsigned char *cmdb)
651 cmdb[0] = 0x1f; /* OM0 - !SECT,!MOD,!DIF,PADP,ECD,CRCP,CRCI,ACOR */
652 cmdb[1] = 0xc3; /* OM1 - DTM,BRST,!CEDM,!SEDM,!DERM,0,AMEX,PSK */
653 cmdb[2] = SPEC_SL; /* OM2 - SL - step pulse low */
654 cmdb[3] = (number_mfm_drives == 1) ? 0x02 : 0x06; /* 1 or 2 drives */
655 cmdb[4] = 0xfc | ((mfm_info[drive].cylinders - 1) >> 8);/* RW time over/high part of number of cylinders */
656 cmdb[5] = mfm_info[drive].cylinders - 1; /* low part of number of cylinders */
657 cmdb[6] = mfm_info[drive].heads - 1; /* Number of heads */
658 cmdb[7] = mfm_info[drive].sectors - 1; /* Number of sectors */
660 cmdb[9] = 0x0a; /* gap length 1 */
661 cmdb[10] = 0x0d; /* gap length 2 */
662 cmdb[11] = 0x0c; /* gap length 3 */
663 cmdb[12] = (mfm_info[drive].precomp - 1) >> 8; /* pre comp cylinder */
664 cmdb[13] = mfm_info[drive].precomp - 1;
665 cmdb[14] = (mfm_info[drive].lowcurrent - 1) >> 8; /* Low current cylinder */
666 cmdb[15] = mfm_info[drive].lowcurrent - 1;
669 static void mfm_specify (void)
671 unsigned char cmdb[16];
673 DBG("specify...dev=%d lastspecified=%d\n", raw_cmd.dev, lastspecifieddrive);
674 mfm_setupspecify (raw_cmd.dev, cmdb);
676 issue_command (CMD_SPC, cmdb, 16);
677 /* Ensure that we will do another specify if we move to the other drive */
678 lastspecifieddrive = raw_cmd.dev;
679 wait_for_completion();
682 static void mfm_seek(void)
684 unsigned char cmdb[4];
687 if (MFM_DRV_INFO.cylinder < 0) {
688 do_mfm = mfm_recal_intr;
689 DBG("mfm_seek: about to call specify\n");
690 mfm_specify (); /* DAG added this */
692 cmdb[0] = raw_cmd.dev + 1;
695 issue_command(CMD_RCLB, cmdb, 2);
698 if (MFM_DRV_INFO.cylinder != raw_cmd.cylinder) {
699 cmdb[0] = raw_cmd.dev + 1;
700 cmdb[1] = 0; /* raw_cmd.head; DAG: My data sheet says this should be 0 */
701 cmdb[2] = raw_cmd.cylinder >> 8;
702 cmdb[3] = raw_cmd.cylinder;
704 do_mfm = mfm_seek_intr;
705 issue_command(CMD_SEK, cmdb, 4);
710 static void mfm_initialise(void)
716 static void request_done(int uptodate)
718 DBG("mfm:request_done\n");
720 unsigned char block[2] = {0, 0};
722 /* Apparently worked - let's check bytes left to DMA */
723 if (hdc63463_dataleft != (PartFragRead_SectorsLeft * 256)) {
724 printk("mfm: request_done - dataleft=%d - should be %d - Eek!\n", hdc63463_dataleft, PartFragRead_SectorsLeft * 256);
725 end_request(CURRENT, 0);
728 /* Potentially this means that we've done; but we might be doing
729 a partial access, (over two cylinders) or we may have a number
730 of fragments in an image file. First let's deal with partial accesss
733 /* Yep - a partial access */
735 /* and issue the remainder */
736 issue_request(PartFragRead_RestartBlock, PartFragRead_SectorsLeft, CURRENT);
740 /* ah well - perhaps there is another fragment to go */
742 /* Increment pointers/counts to start of next fragment */
743 if (SectorsLeftInRequest > 0) printk("mfm: SectorsLeftInRequest>0 - Eek! Shouldn't happen!\n");
745 /* No - its the end of the line */
746 /* end_request's should have happened at the end of sector DMAs */
747 /* Turns Drive LEDs off - may slow it down? */
748 if (!elv_next_request(QUEUE))
749 issue_command(CMD_CKV, block, 2);
752 DBG("request_done: About to mfm_request\n");
753 /* Next one please */
754 mfm_request(); /* Moved from mfm_rw_intr */
755 DBG("request_done: returned from mfm_request\n");
757 printk("mfm:request_done: update=0\n");
758 end_request(CURRENT, 0);
763 static void error_handler(void)
765 printk("error detected... status = ");
768 if (*errors > MFM_DRV_INFO.errors.abort)
770 if (*errors > MFM_DRV_INFO.errors.recal)
771 MFM_DRV_INFO.cylinder = NEED_2_RECAL;
774 static void rw_interrupt(void)
776 printk("rw_interrupt\n");
779 static struct cont rw_cont =
788 * Actually gets round to issuing the request - note everything at this
789 * point is in 256 byte sectors not Linux 512 byte blocks
791 static void issue_request(unsigned int block, unsigned int nsect,
794 struct gendisk *disk = req->rq_disk;
795 struct mfm_info *p = disk->private_data;
796 int track, start_head, start_sector;
797 int sectors_to_next_cyl;
800 track = block / p->sectors;
801 start_sector = block % p->sectors;
802 start_head = track % p->heads;
804 /* First get the number of whole tracks which are free before the next
806 sectors_to_next_cyl = (p->heads - (start_head + 1)) * p->sectors;
807 /* Then add in the number of sectors left on this track */
808 sectors_to_next_cyl += (p->sectors - start_sector);
810 DBG("issue_request: mfm_info[dev].sectors=%d track=%d\n", p->sectors, track);
813 raw_cmd.sector = start_sector;
814 raw_cmd.head = start_head;
815 raw_cmd.cylinder = track / p->heads;
816 raw_cmd.cmdtype = CURRENT->cmd;
817 raw_cmd.cmdcode = CURRENT->cmd == WRITE ? CMD_WD : CMD_RD;
818 raw_cmd.cmddata[0] = dev + 1; /* DAG: +1 to get US */
819 raw_cmd.cmddata[1] = raw_cmd.head;
820 raw_cmd.cmddata[2] = raw_cmd.cylinder >> 8;
821 raw_cmd.cmddata[3] = raw_cmd.cylinder;
822 raw_cmd.cmddata[4] = raw_cmd.head;
823 raw_cmd.cmddata[5] = raw_cmd.sector;
825 /* Was == and worked - how the heck??? */
826 if (lastspecifieddrive != raw_cmd.dev)
829 if (nsect <= sectors_to_next_cyl) {
830 raw_cmd.cmddata[6] = nsect >> 8;
831 raw_cmd.cmddata[7] = nsect;
832 PartFragRead = 0; /* All in one */
833 PartFragRead_SectorsLeft = 0; /* Must set this - used in DMA calcs */
835 raw_cmd.cmddata[6] = sectors_to_next_cyl >> 8;
836 raw_cmd.cmddata[7] = sectors_to_next_cyl;
837 PartFragRead = sectors_to_next_cyl; /* only do this many this time */
838 PartFragRead_RestartBlock = block + sectors_to_next_cyl; /* Where to restart from */
839 PartFragRead_SectorsLeft = nsect - sectors_to_next_cyl;
843 /* Setup DMA pointers */
844 hdc63463_dataptr = (unsigned int) Copy_buffer;
845 hdc63463_dataleft = nsect * 256; /* Better way? */
847 DBG("mfm%c: %sing: CHS=%d/%d/%d, sectors=%d, buffer=0x%08lx (%p)\n",
848 raw_cmd.dev + 'a', (CURRENT->cmd == READ) ? "read" : "writ",
851 raw_cmd.sector, nsect, (unsigned long) Copy_buffer, CURRENT);
854 errors = &(CURRENT->errors);
856 mfm_tq.routine = (void (*)(void *)) mfm_initialise;
857 queue_task(&mfm_tq, &tq_immediate);
858 mark_bh(IMMEDIATE_BH);
862 } /* issue_request */
865 * Called when an error has just happened - need to trick mfm_request
866 * into thinking we weren't busy
868 * Turn off ints - mfm_request expects them this way
870 static void mfm_rerequest(void)
872 DBG("mfm_rerequest\n");
878 static struct gendisk *mfm_gendisk[2];
880 static void mfm_request(void)
882 DBG("mfm_request CURRENT=%p Busy=%d\n", CURRENT, Busy);
884 /* If we are still processing then return; we will get called again */
886 /* Again seems to be common in 1.3.45 */
887 /*DBG*/printk("mfm_request: Exiting due to busy\n");
893 unsigned int block, nsect;
894 struct gendisk *disk;
896 DBG("mfm_request: loop start\n");
899 DBG("mfm_request: before !CURRENT\n");
902 printk("mfm_request: Exiting due to empty queue (pre)\n");
908 DBG("mfm_request: before arg extraction\n");
910 disk = CURRENT->rq_disk;
911 block = CURRENT->sector;
912 nsect = CURRENT->nr_sectors;
913 if (block >= get_capacity(disk) ||
914 block+nsect > get_capacity(disk)) {
915 printk("%s: bad access: block=%d, count=%d, nr_sects=%ld\n",
916 disk->disk_name, block, nsect, get_capacity(disk));
917 printk("mfm: continue 1\n");
918 end_request(CURRENT, 0);
923 /* DAG: Linux doesn't cope with this - even though it has an array telling
924 it the hardware block size - silly */
925 block <<= 1; /* Now in 256 byte sectors */
926 nsect <<= 1; /* Ditto */
928 SectorsLeftInRequest = nsect >> 1;
929 Sectors256LeftInCurrent = CURRENT->current_nr_sectors * 2;
930 Copy_buffer = CURRENT->buffer;
931 Copy_Sector = CURRENT->sector << 1;
933 DBG("mfm_request: block after offset=%d\n", block);
935 if (CURRENT->cmd != READ && CURRENT->cmd != WRITE) {
936 printk("unknown mfm-command %d\n", CURRENT->cmd);
937 end_request(CURRENT, 0);
939 printk("mfm: continue 4\n");
942 issue_request(block, nsect, CURRENT);
946 DBG("mfm_request: Dropping out bottom\n");
949 static void do_mfm_request(request_queue_t *q)
951 DBG("do_mfm_request: about to mfm_request\n");
955 static void mfm_interrupt_handler(int unused, void *dev_id, struct pt_regs *regs)
957 void (*handler) (void) = do_mfm;
961 DBG("mfm_interrupt_handler (handler=0x%p)\n", handler);
963 mfm_status = inw(MFM_STATUS);
965 /* If CPR (Command Parameter Reject) and not busy it means that the command
966 has some return message to give us */
967 if ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR) {
971 in = inw(MFM_DATAIN);
972 result[len++] = in >> 8;
980 outw (CMD_RCAL, MFM_COMMAND); /* Clear interrupt condition */
981 printk ("mfm: unexpected interrupt - status = ");
991 * Tell the user about the drive if we decided it exists.
993 static void mfm_geometry(int drive)
995 struct mfm_info *p = mfm_info + drive;
996 struct gendisk *disk = mfm_gendisk[drive];
997 disk->private_data = p;
999 printk ("%s: %dMB CHS=%d/%d/%d LCC=%d RECOMP=%d\n",
1001 p->cylinders * p->heads * p->sectors / 4096,
1002 p->cylinders, p->heads, p->sectors,
1003 p->lowcurrent, p->precomp);
1004 set_capacity(disk, p->cylinders * p->heads * p->sectors / 2);
1007 #ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
1009 * Attempt to detect a drive and find its geometry. The drive has already been
1012 * We first recalibrate the disk, then try to probe sectors, heads and then
1013 * cylinders. NOTE! the cylinder probe may break drives. The xd disk driver
1014 * does something along these lines, so I assume that most drives are up to
1015 * this mistreatment...
1017 static int mfm_detectdrive (int drive)
1019 unsigned int mingeo[3], maxgeo[3];
1020 unsigned int attribute, need_recal = 1;
1021 unsigned char cmdb[8];
1023 memset (mingeo, 0, sizeof (mingeo));
1024 maxgeo[0] = mfm_info[drive].sectors;
1025 maxgeo[1] = mfm_info[drive].heads;
1026 maxgeo[2] = mfm_info[drive].cylinders;
1028 cmdb[0] = drive + 1;
1031 for (attribute = 0; attribute < 3; attribute++) {
1032 while (mingeo[attribute] != maxgeo[attribute]) {
1033 unsigned int variable;
1035 variable = (maxgeo[attribute] + mingeo[attribute]) >> 1;
1036 cmdb[1] = cmdb[2] = cmdb[3] = cmdb[4] = cmdb[5] = 0;
1042 issue_command (CMD_RCLB, cmdb, 2);
1043 wait_for_completion ();
1044 wait_for_command_end ();
1045 if (result[1] == 0x20)
1047 } while (result[1] && --tries);
1049 outw (CMD_RCAL, MFM_COMMAND);
1055 switch (attribute) {
1058 issue_command (CMD_CMPD, cmdb, 8);
1063 issue_command (CMD_CMPD, cmdb, 8);
1066 cmdb[2] = variable >> 8;
1068 issue_command (CMD_SEK, cmdb, 4);
1071 wait_for_completion ();
1072 wait_for_command_end ();
1074 switch (result[1]) {
1077 mingeo[attribute] = variable + 1;
1081 outw (CMD_RCAL, MFM_COMMAND);
1087 maxgeo[attribute] = variable;
1092 mfm_info[drive].cylinders = mingeo[2];
1093 mfm_info[drive].lowcurrent = mingeo[2];
1094 mfm_info[drive].precomp = mingeo[2] / 2;
1095 mfm_info[drive].heads = mingeo[1];
1096 mfm_info[drive].sectors = mingeo[0];
1097 outw (CMD_RCAL, MFM_COMMAND);
1103 * Initialise all drive information for this controller.
1105 static int mfm_initdrives(void)
1109 if (number_mfm_drives > MFM_MAXDRIVES) {
1110 number_mfm_drives = MFM_MAXDRIVES;
1111 printk("No. of ADFS MFM drives is greater than MFM_MAXDRIVES - you can't have that many!\n");
1114 for (drive = 0; drive < number_mfm_drives; drive++) {
1115 mfm_info[drive].lowcurrent = 1;
1116 mfm_info[drive].precomp = 1;
1117 mfm_info[drive].cylinder = -1;
1118 mfm_info[drive].errors.recal = 0;
1119 mfm_info[drive].errors.report = 0;
1120 mfm_info[drive].errors.abort = 4;
1122 #ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
1123 mfm_info[drive].cylinders = 1024;
1124 mfm_info[drive].heads = 8;
1125 mfm_info[drive].sectors = 64;
1127 unsigned char cmdb[16];
1129 mfm_setupspecify (drive, cmdb);
1131 issue_command (CMD_SPC, cmdb, 16);
1132 wait_for_completion ();
1133 if (!mfm_detectdrive (drive)) {
1134 mfm_info[drive].cylinders = 0;
1135 mfm_info[drive].heads = 0;
1136 mfm_info[drive].sectors = 0;
1138 cmdb[0] = cmdb[1] = 0;
1139 issue_command (CMD_CKV, cmdb, 2);
1142 mfm_info[drive].cylinders = 1; /* its going to have to figure it out from the partition info */
1143 mfm_info[drive].heads = 4;
1144 mfm_info[drive].sectors = 32;
1147 return number_mfm_drives;
1153 * The 'front' end of the mfm driver follows...
1156 static int mfm_ioctl(struct inode *inode, struct file *file, u_int cmd, u_long arg)
1158 struct mfm_info *p = inode->i_bdev->bd_disk->private_data;
1159 struct hd_geometry *geo = (struct hd_geometry *) arg;
1160 if (cmd != HDIO_GETGEO)
1164 if (put_user (p->heads, &geo->heads))
1166 if (put_user (p->sectors, &geo->sectors))
1168 if (put_user (p->cylinders, &geo->cylinders))
1170 if (put_user (get_start_sect(inode->i_bdev), &geo->start))
1176 * This is to handle various kernel command line parameters
1177 * specific to this driver.
1179 void mfm_setup(char *str, int *ints)
1185 * Set the CHS from the ADFS boot block if it is present. This is not ideal
1186 * since if there are any non-ADFS partitions on the disk, this won't work!
1187 * Hence, I want to get rid of this...
1189 void xd_set_geometry(struct block_device *bdev, unsigned char secsptrack,
1190 unsigned char heads, unsigned int secsize)
1192 struct mfm_info *p = bdev->bd_disk->private_data;
1193 int drive = p - mfm_info;
1194 unsigned long disksize = bdev->bd_inode->i_size;
1196 if (p->cylinders == 1) {
1197 p->sectors = secsptrack;
1199 p->cylinders = discsize / (secsptrack * heads * secsize);
1201 if ((heads < 1) || (p->cylinders > 1024)) {
1202 printk("%s: Insane disc shape! Setting to 512/4/32\n",
1203 bdev->bd_disk->disk_name);
1205 /* These values are fairly arbitary, but are there so that if your
1206 * lucky you can pick apart your disc to find out what is going on -
1207 * I reckon these figures won't hurt MOST drives
1213 if (raw_cmd.dev == drive)
1215 mfm_geometry (drive);
1219 static struct block_device_operations mfm_fops =
1221 .owner = THIS_MODULE,
1226 * See if there is a controller at the address presently at mfm_addr
1228 * We check to see if the controller is busy - if it is, we abort it first,
1229 * and check that the chip is no longer busy after at least 180 clock cycles.
1230 * We then issue a command and check that the BSY or CPR bits are set.
1232 static int mfm_probecontroller (unsigned int mfm_addr)
1234 if (inw (MFM_STATUS) & STAT_BSY) {
1235 outw (CMD_ABT, MFM_COMMAND);
1237 if (inw (MFM_STATUS) & STAT_BSY)
1241 if (inw (MFM_STATUS) & STAT_CED)
1242 outw (CMD_RCAL, MFM_COMMAND);
1244 outw (CMD_SEK, MFM_COMMAND);
1246 if (inw (MFM_STATUS) & (STAT_BSY | STAT_CPR)) {
1247 unsigned int count = 2000;
1248 while (inw (MFM_STATUS) & STAT_BSY) {
1254 outw (CMD_RCAL, MFM_COMMAND);
1259 static int mfm_do_init(unsigned char irqmask)
1263 printk("mfm: found at address %08X, interrupt %d\n", mfm_addr, mfm_irq);
1266 if (!request_region (mfm_addr, 10, "mfm"))
1269 ret = register_blkdev(MAJOR_NR, "mfm");
1273 /* Stuff for the assembler routines to get to */
1274 hdc63463_baseaddress = ioaddr(mfm_addr);
1275 hdc63463_irqpolladdress = mfm_IRQPollLoc;
1276 hdc63463_irqpollmask = irqmask;
1278 mfm_queue = blk_init_queue(do_mfm_request, &mfm_lock);
1283 lastspecifieddrive = -1;
1285 mfm_drives = mfm_initdrives();
1291 for (i = 0; i < mfm_drives; i++) {
1292 struct gendisk *disk = alloc_disk(64);
1295 disk->major = MAJOR_NR;
1296 disk->first_minor = i << 6;
1297 disk->fops = &mfm_fops;
1298 sprintf(disk->disk_name, "mfm%c", 'a'+i);
1299 mfm_gendisk[i] = disk;
1302 printk("mfm: detected %d hard drive%s\n", mfm_drives,
1303 mfm_drives == 1 ? "" : "s");
1304 ret = request_irq(mfm_irq, mfm_interrupt_handler, SA_INTERRUPT, "MFM harddisk", NULL);
1306 printk("mfm: unable to get IRQ%d\n", mfm_irq);
1311 outw(0x80, mfm_irqenable); /* Required to enable IRQs from MFM podule */
1313 for (i = 0; i < mfm_drives; i++) {
1315 mfm_gendisk[i]->queue = mfm_queue;
1316 add_disk(mfm_gendisk[i]);
1321 for (i = 0; i < mfm_drives; i++)
1322 put_disk(mfm_gendisk[i]);
1324 blk_cleanup_queue(mfm_queue);
1326 unregister_blkdev(MAJOR_NR, "mfm");
1328 release_region(mfm_addr, 10);
1333 put_disk(mfm_gendisk[i]);
1337 static void mfm_do_exit(void)
1341 free_irq(mfm_irq, NULL);
1342 for (i = 0; i < mfm_drives; i++) {
1343 del_gendisk(mfm_gendisk[i]);
1344 put_disk(mfm_gendisk[i]);
1346 blk_cleanup_queue(mfm_queue);
1347 unregister_blkdev(MAJOR_NR, "mfm");
1349 release_region(mfm_addr, 10);
1352 static int __devinit mfm_probe(struct expansion_card *ec, struct ecard_id *id)
1357 mfm_addr = ecard_address(ec, ECARD_IOC, ECARD_MEDIUM) + 0x800;
1358 mfm_IRQPollLoc = ioaddr(mfm_addr + 0x400);
1359 mfm_irqenable = mfm_IRQPollLoc;
1362 return mfm_do_init(0x08);
1365 static void __devexit mfm_remove(struct expansion_card *ec)
1367 outw (0, mfm_irqenable); /* Required to enable IRQs from MFM podule */
1371 static const struct ecard_id mfm_cids[] = {
1372 { MANU_ACORN, PROD_ACORN_MFM },
1376 static struct ecard_driver mfm_driver = {
1378 .remove = __devexit(mfm_remove),
1379 .id_table = mfm_cids,
1386 * Look for a MFM controller - first check the motherboard, then the podules
1387 * The podules have an extra interrupt enable that needs to be played with
1389 * The HDC is accessed at MEDIUM IOC speeds.
1391 static int __init mfm_init (void)
1393 unsigned char irqmask;
1395 if (mfm_probecontroller(ONBOARD_MFM_ADDRESS)) {
1396 mfm_addr = ONBOARD_MFM_ADDRESS;
1397 mfm_IRQPollLoc = IOC_IRQSTATB;
1399 mfm_irq = IRQ_HARDDISK;
1400 return mfm_do_init(0x08); /* IL3 pin */
1402 return ecard_register_driver(&mfm_driver);
1406 static void __exit mfm_exit(void)
1408 if (mfm_addr == ONBOARD_MFM_ADDRESS)
1411 ecard_unregister_driver(&mfm_driver);
1414 module_init(mfm_init)
1415 module_exit(mfm_exit)
1416 MODULE_LICENSE("GPL");